A new beam splitter for matter waves

Beam splitters are fundamental tools in optics, and enable
the construction of many interferometric devices. In order to control matter waves as well as light waves, it is therefore important to be able to construct matter wave beam splitters.
A novel possibility for such a device has been proposed
and demonstrated by a collaboration between
Bertrand Georgeot of LPT and the experimental cold atoms group of LCAR (group of David Guery-Odelin).
In the proposed setup, the matter wave is a guided atom laser that can be tuned from quasi-monomode to a regime where many transverse modes are populated, and propagates in a horizontal dipole beam until it crosses another horizontal beam at 45 degrees. Depending on the parameters, the system can act as a perfect switch, or as a beam splitter in which several exit channels are populated. The splitting regime results from a chaotic scattering dynamics.
The results have
been published recently in Physical Review Letters , where the paper
was selected as an Editor’s suggestion and gave rise to a synopsis in
the APS highlight journal ``Physics’’.